Re: a simple spur fix

Mike Woods

My guess is that the two intended filter frequencies are:  90Mhz (second harmonic of 45MHz 1st LO) and 12MHz (2nd LO).  The parts represent the right values for a filter at 90MHz, but it seems that 30M band would be wiped out by the second of the mods (which somebody has already observed).   12MHz should be being wiped out instead, so I suspect a typo.

Perhaps  either a 35pF capacitor and the 5µH inductor as stated or a 3.8µH inductor and the 47pF capacitor as stated being about right for getting the filter resonant just on the low side of 12MHz.

Mike ZL1AXG

On 10/11/18 9:49 AM, Brian L. Davis wrote:
10pf series with .3uhy - resonant about 91 MHz
47pf series with 5.0uhy resonant about 10.4 MHz
Is this correct?
Brian - WA5RDG

--
Mike Woods
mhwoods@...

Re: a simple spur fix

Jerry Gaffke

Allison,

I'm not 100% sure what his LC traps are doing, but they may not have to move around.
My best guess is that the one at TP13 (tuned to around 90mhz)
just removes the 2'd harmonic of the 45mhz IF that gets created by those 2n3904's
running flat out.  It doesn't have to move.

Example:  Transmitting at 21mhz, clk2 is at 45+21=66mhz.
If any 2*45=90mhz energy is present, it mixes with the 66mhz clk1 at D1,D2 to create a 90-66 = 24mhz spur.

Farhan suggests the second LC trap is to suppress the 12mhz BFO energy due to crosstalk between clk0 and clk2.
Though we have a report that this also sucks out 10mhz reception, so either that particular example is tuned
differently than Farhan's, or that's an awfully wide trap, or I don't know what's going on there.

If these mods are easily reproducible for acceptable results, good enough by me.
We'll see.

Jerry

On Fri, Nov 9, 2018 at 02:45 PM, ajparent1/KB1GMX wrote:
Your doing what I tried back in June/July time frame, it failed then.

Reason first series traps good enough to suck out the spur at a given frequency
are narrow enough  to be only a spot frequency fix.  The 2IF-LO spur for 28mhz
BAND is between 17 to 16 mhz for 10M alone.  So you need a series trap that
can not do a band.

The other issue is the power amp.  At 80M and 10W out the gain is about 60db
but as you go up, at 20M the gain is down to ~56db, and at 10M the gain is maybe
~52DB.   So at the spur frequency you have more gain available than the desired
output frequency and the differential gain is enough to put that spur as shown at
-45db at more like -37db below 2W.

The fix has to be more comprehensive.  Also it must be field verifiable or factory
set to allow for 1 or 5% parts.

The 45mhz section needs:
45mhz filter inductors shielded or better that section relocated.
Amplifier distortion clean up.
Swap the 45mhz port and LO ports as IF ports are most sensitive to mismatch.

A thought to look into...
Replace the TIA amp at 45mhz with a more common resistive feedback amp (typical 2n5109 amp)
with 20db gain.  Here is the hint:  Often when that amp is shown due to the fact that changes at either
port impact the opposing port they often have a 6db pad at the output.  However for the TX case that
same pad can be at the input and it insures the 45mhz filter will have a good match for the network
and the transistor with its input impedance stable will have output stability going to the mixer.

Allison

Re: a simple spur fix

Jerry Gaffke

Good!  Sounds like it's working!  ;-)
I for one am willing to give up 30m on what is mostly an SSB rig.

If you were planning to operate CW on 30m, you could put a couple pins and a jumper
in series with that C+L.  So with the jumper out, the mod is undone.
Transmitting CW we don't have trouble with spurs, since the BFO and clk1 are both shut down.
The only RF floating about the rig is clk2 at the transmit frequency.

Jerry, KE7ER

On Fri, Nov 9, 2018 at 03:03 PM, barry halterman wrote:
I installed the series trap across C202 in the LPF and it reduced the 30 meter sensitivity drastically.

Re: a simple spur fix

barry halterman

I installed the series trap across C202 in the LPF and it reduced the 30 meter sensitivity drastically.

On Fri, Nov 9, 2018, 5:46 PM ajparent1/KB1GMX <kb1gmx@... wrote:
Farhan,

Your doing what I tried back in June/July time frame, it failed then.

Reason first series traps good enough to suck out the spur at a given frequency
are narrow enough  to be only a spot frequency fix.  The 2IF-LO spur for 28mhz
BAND is between 17 to 16 mhz for 10M alone.  So you need a series trap that
can not do a band.

The other issue is the power amp.  At 80M and 10W out the gain is about 60db
but as you go up, at 20M the gain is down to ~56db, and at 10M the gain is maybe
~52DB.   So at the spur frequency you have more gain available than the desired
output frequency and the differential gain is enough to put that spur as shown at
-45db at more like -37db below 2W.

The fix has to be more comprehensive.  Also it must be field verifiable or factory
set to allow for 1 or 5% parts.

The 45mhz section needs:
45mhz filter inductors shielded or better that section relocated.
Amplifier distortion clean up.
Swap the 45mhz port and LO ports as IF ports are most sensitive to mismatch.

A thought to look into...
Replace the TIA amp at 45mhz with a more common resistive feedback amp (typical 2n5109 amp)
with 20db gain.  Here is the hint:  Often when that amp is shown due to the fact that changes at either
port impact the opposing port they often have a 6db pad at the output.  However for the TX case that
same pad can be at the input and it insures the 45mhz filter will have a good match for the network
and the transistor with its input impedance stable will have output stability going to the mixer.

Allison

Re: uBITX AGC - Adafruit TPA2016, A Success!

Jim Sheldon

I don't know. Check the T_DO and T_CS pins on the test set and see if one of the connected to the same input pin on the Teensy as the encoder SW.

On Nov 8, 2018, at 1:23 PM, John Scherer <jrsphoto@...> wrote:

Wow, just found this thread.  I currently use the nd6t AGC and as playing around with controlling the hang-time digitally, but it takes 6 pins.  I just placed an order for the TPA2016 so I'll be playing with this for sure.  It would be really awesome if KD8CEC (or anyone) could add a config page for this to the Nextion display and support for it CEC firmware!  I'd take a stab at it but after looking at the graphics editor for the Nextion display, I'll pass.  It'd take me weeks to figure that hot mess out ;-)

John - N0CTL

Re: Transmit Problem

Bill Cromwell

Hi Wayne,

Shielding can be added to the interior of those "attractive plastic boxes". I made my own steel box from new steel. But I have used the aluminum foil lining inside wood or plastic boxes, The heavier foil pans that are sold for baking or the ones frozen meals come in are much sturdier than the paper thin foil sold for wrapping food.

73,

Bill KU8H

On 11/9/18 5:20 PM, Lawrence Galea wrote:
Have you tried putting the amplifier on the back panel?
On Fri, Nov 9, 2018 at 5:59 AM Wayne Leake <wayneleake@... <mailto:wayneleake@...>> wrote:
Regarding the shielded enclosures, yup, most good radios are
enclosed in metal cases.
Receiver only is far less fussy.
I was looking at a number of possible cases for my BITX, and
decided on a BUD enclosure, all aluminum
It is big enough for the HF Signal BITX40, but turns out not for
another BITX I am assembling.
Boards too wide to fit both exciter and PA boards in it.
I see all these great looking plastic cases, but figured that I do
not want to go with no shielding.
Hence the one that will go into a cassette  deck case will have
shielding.
The ferrite beads have their places, but don't take the place of
good shielding, which may also help prevent images and harmonics ,
plus spurs, from escaping.
YMMV
Wayne WA2YNE
--
bark less - wag more

Re: a simple spur fix

ajparent1/kb1gmx

Farhan,

Your doing what I tried back in June/July time frame, it failed then.

Reason first series traps good enough to suck out the spur at a given frequency
are narrow enough  to be only a spot frequency fix.  The 2IF-LO spur for 28mhz
BAND is between 17 to 16 mhz for 10M alone.  So you need a series trap that
can not do a band.

The other issue is the power amp.  At 80M and 10W out the gain is about 60db
but as you go up, at 20M the gain is down to ~56db, and at 10M the gain is maybe
~52DB.   So at the spur frequency you have more gain available than the desired
output frequency and the differential gain is enough to put that spur as shown at
-45db at more like -37db below 2W.

The fix has to be more comprehensive.  Also it must be field verifiable or factory
set to allow for 1 or 5% parts.

The 45mhz section needs:
45mhz filter inductors shielded or better that section relocated.
Amplifier distortion clean up.
Swap the 45mhz port and LO ports as IF ports are most sensitive to mismatch.

A thought to look into...
Replace the TIA amp at 45mhz with a more common resistive feedback amp (typical 2n5109 amp)
with 20db gain.  Here is the hint:  Often when that amp is shown due to the fact that changes at either
port impact the opposing port they often have a 6db pad at the output.  However for the TX case that
same pad can be at the input and it insures the 45mhz filter will have a good match for the network
and the transistor with its input impedance stable will have output stability going to the mixer.

Allison

Re: Transmit Problem

Lawrence Galea

Have you tried putting the amplifier on the back panel?

On Fri, Nov 9, 2018 at 5:59 AM Wayne Leake <wayneleake@...> wrote:
Regarding the shielded enclosures, yup, most good radios are enclosed in metal cases.
Receiver only is far less fussy.
I was looking at a number of possible cases for my BITX, and decided on a BUD enclosure, all aluminum
It is big enough for the HF Signal BITX40, but turns out not for another BITX I am assembling.
Boards too wide to fit both exciter and PA boards in it.
I see all these great looking plastic cases, but figured that I do not want to go with no shielding.
Hence the one that will go into a cassette  deck case will have shielding.
The ferrite beads have their places, but don't take the place of good shielding, which may also help prevent images and harmonics , plus spurs, from escaping.
YMMV
Wayne WA2YNE

MONEYSMITH

I WANT TO BUY  "The Raduino board with Si5351, Arduino Nano. Fully tested AND PROGRAMMED." I DON'T NEED THE LCD READOUT.

HOW MUCH AND WHERE CAN I ORDER?

WILLIAM

On 11/9/2018 1:32 PM, MONEYSMITH wrote:
THANK YOU

On 11/9/2018 1:21 PM, Vince Vielhaber wrote:
The crystal is on the green board under the display.  Unplug the display and you'll see it.

Vince.

On 11/09/2018 03:26 PM, MONEYSMITH wrote:
THIS BOARD HAS A MEGA328P CHIP. I HAVE NO INFORMATION ON THE BOARD.

I FOUND NO SI5351A CHIP?

PHOTOS ATTACHED.

W4NFR

On 11/9/2018 11:42 AM, Arv Evans wrote:
Bill W4NFR

The picture you provided is the back side of an Arduino Nano board.
The crystals on this PCB
have nothing to do with the transmitting frequency of your
transceiver.  The SI5351a frequency
synthesizer is a small 10-pin MSOP IC, or 20-pin QFN IC.  It should be
clearly labeled on the
top as an Si5351A device.  Do you have a picture of the Raduino board
with its Si5351A chip
and crystal?

Arv  K7HKL
_._

On Fri, Nov 9, 2018 at 11:20 AM MONEYSMITH <w4nfr@...
<mailto:w4nfr@...>> wrote:

HERE IS A PHOTO OF BOARD AND CRYSTAL.

W4NFR

On 11/9/2018 9:57 AM, Mvs Sarma wrote:
OMG. acidentally crept in perhaps .

regards
sarma
vu3zmv

On Fri, Nov 9, 2018 at 10:50 PM MONEYSMITH <w4nfr@...
<mailto:w4nfr@...>> wrote:

I OPENED UP MY uBITX  AND TOOK A LOOK AT THE S1535A BOARD.
THE CRYSTAL HAS 20.0 STAMPED ON IT INSTEAD OF 25.0 MHZ?

On 11/8/2018 5:59 PM, RCC WB5YYM wrote:

------------------------------------------------------------------------

AVG logo <https://www.avg.com/internet-security>

This email has been checked for viruses by AVG antivirus
software.
www.avg.com <https://www.avg.com/internet-security>

---
This email has been checked for viruses by AVG.
https://www.avg.com

MONEYSMITH

THANK YOU

On 11/9/2018 1:21 PM, Vince Vielhaber wrote:
The crystal is on the green board under the display.  Unplug the display and you'll see it.

Vince.

On 11/09/2018 03:26 PM, MONEYSMITH wrote:
THIS BOARD HAS A MEGA328P CHIP. I HAVE NO INFORMATION ON THE BOARD.

I FOUND NO SI5351A CHIP?

PHOTOS ATTACHED.

W4NFR

On 11/9/2018 11:42 AM, Arv Evans wrote:
Bill W4NFR

The picture you provided is the back side of an Arduino Nano board.
The crystals on this PCB
have nothing to do with the transmitting frequency of your
transceiver.  The SI5351a frequency
synthesizer is a small 10-pin MSOP IC, or 20-pin QFN IC.  It should be
clearly labeled on the
top as an Si5351A device.  Do you have a picture of the Raduino board
with its Si5351A chip
and crystal?

Arv  K7HKL
_._

On Fri, Nov 9, 2018 at 11:20 AM MONEYSMITH <w4nfr@...
<mailto:w4nfr@...>> wrote:

HERE IS A PHOTO OF BOARD AND CRYSTAL.

W4NFR

On 11/9/2018 9:57 AM, Mvs Sarma wrote:
OMG. acidentally crept in perhaps .

regards
sarma
vu3zmv

On Fri, Nov 9, 2018 at 10:50 PM MONEYSMITH <w4nfr@...
<mailto:w4nfr@...>> wrote:

I OPENED UP MY uBITX  AND TOOK A LOOK AT THE S1535A BOARD.
THE CRYSTAL HAS 20.0 STAMPED ON IT INSTEAD OF 25.0 MHZ?

On 11/8/2018 5:59 PM, RCC WB5YYM wrote:

------------------------------------------------------------------------

AVG logo <https://www.avg.com/internet-security>

This email has been checked for viruses by AVG antivirus
software.
www.avg.com <https://www.avg.com/internet-security>

---
This email has been checked for viruses by AVG.
https://www.avg.com

Vince Vielhaber

The crystal is on the green board under the display. Unplug the display and you'll see it.

Vince.

On 11/09/2018 03:26 PM, MONEYSMITH wrote:
THIS BOARD HAS A MEGA328P CHIP. I HAVE NO INFORMATION ON THE BOARD.

I FOUND NO SI5351A CHIP?

PHOTOS ATTACHED.

W4NFR

On 11/9/2018 11:42 AM, Arv Evans wrote:
Bill W4NFR

The picture you provided is the back side of an Arduino Nano board.
The crystals on this PCB
have nothing to do with the transmitting frequency of your
transceiver. The SI5351a frequency
synthesizer is a small 10-pin MSOP IC, or 20-pin QFN IC. It should be
clearly labeled on the
top as an Si5351A device. Do you have a picture of the Raduino board
with its Si5351A chip
and crystal?

Arv K7HKL
_._

On Fri, Nov 9, 2018 at 11:20 AM MONEYSMITH <w4nfr@...
<mailto:w4nfr@...>> wrote:

HERE IS A PHOTO OF BOARD AND CRYSTAL.

W4NFR

On 11/9/2018 9:57 AM, Mvs Sarma wrote:
OMG. acidentally crept in perhaps .

regards
sarma
vu3zmv

On Fri, Nov 9, 2018 at 10:50 PM MONEYSMITH <w4nfr@...
<mailto:w4nfr@...>> wrote:

I OPENED UP MY uBITX AND TOOK A LOOK AT THE S1535A BOARD.
THE CRYSTAL HAS 20.0 STAMPED ON IT INSTEAD OF 25.0 MHZ?

On 11/8/2018 5:59 PM, RCC WB5YYM wrote:

------------------------------------------------------------------------
AVG logo <https://www.avg.com/internet-security>

This email has been checked for viruses by AVG antivirus
software.
www.avg.com <https://www.avg.com/internet-security>

Re: a simple spur fix

Timothy Fidler

Yup.  it is correct.  The easiest way to get the units right is  L in uH , C in uF and result will be in Mhz  ie recip of sqrt of micro x micro .

But remember when you are working at VHF with 5 percent capacitors and air wound coils,  even Tiny errors or tolerances  will put you off by 100s of KHz.  Ditto temperature effects on components.

Timothy E. Fidler : Engineer BE Mech(1) Auckland , NDT specialist AINDT UT /RT3 , MT2 CB #2885,
Telephone Whangarei   022  691 8405
e: Engstr@...

----- Original Message -----
From:
BITX20@groups.io

To:
<BITX20@groups.io>
Cc:

Sent:
Fri, 09 Nov 2018 12:49:44 -0800
Subject:
Re: [BITX20] a simple spur fix

10pf series with .3uhy - resonant about 91 MHz
47pf series with 5.0uhy resonant about 10.4 MHz
Is this correct?
Brian - WA5RDG

Re: a simple spur fix

Ashhar:

You give the number of turns necessary, and the core IDs, but what is the gauge of wire used???

David A Posthuma, WD8PUO

1 (616) 283-7703

From: BITX20@groups.io <BITX20@groups.io> On Behalf Of Ashhar Farhan
Sent: Friday, November 09, 2018 10:35 AM
To: bitx20@groups.io
Subject: [BITX20] a simple spur fix

so, there is one spur fix that is now consistently working for me.

among rhe solutions, i was looking for one that would be easy to apply.

first, the distortion in the 45 mhz amp is creating harmonic distortion. so a 0.3uh in series with a 10 pf is used across TP13 (output of the 45 MHz IF amp going to the front end mixer). 8 turns on T30-6 gives you 300nh.

second, there is a cross talk inside the Si5351 where the 12 mhz from the bfo leaks into the local oscillator. A 5uh in series with a 47 pf across C202 of the LPF will suppress it. 35 turns on T30-6 gives you 5uh.

- f

Evan Hand

The Si5351 is on the back side of the board in the first picture, between the display and the board that the ATmeg board plugs into.  The board with the plug is the Raduino board.

On Fri, Nov 9, 2018 at 2:27 PM MONEYSMITH <w4nfr@...> wrote:

THIS BOARD HAS A MEGA328P CHIP. I HAVE NO INFORMATION ON THE BOARD.

I FOUND NO SI5351A CHIP?

PHOTOS ATTACHED.

W4NFR

On 11/9/2018 11:42 AM, Arv Evans wrote:
Bill W4NFR

The picture you provided is the back side of an Arduino Nano board.  The crystals on this PCB
have nothing to do with the transmitting frequency of your transceiver.  The SI5351a frequency
synthesizer is a small 10-pin MSOP IC, or 20-pin QFN IC.  It should be clearly labeled on the
top as an Si5351A device.  Do you have a picture of the Raduino board with its Si5351A chip
and crystal?

Arv  K7HKL
_._

On Fri, Nov 9, 2018 at 11:20 AM MONEYSMITH <w4nfr@...> wrote:

HERE IS A PHOTO OF BOARD AND CRYSTAL.

W4NFR

On 11/9/2018 9:57 AM, Mvs Sarma wrote:
OMG. acidentally crept in perhaps .

regards
sarma
vu3zmv

On Fri, Nov 9, 2018 at 10:50 PM MONEYSMITH <w4nfr@...> wrote:

I OPENED UP MY uBITX  AND TOOK A LOOK AT THE S1535A BOARD. THE CRYSTAL HAS 20.0 STAMPED ON IT INSTEAD OF 25.0 MHZ?

On 11/8/2018 5:59 PM, RCC WB5YYM wrote:

 This email has been checked for viruses by AVG antivirus software. www.avg.com

Re: a simple spur fix

Brian L. Davis

10pf series with .3uhy - resonant about 91 MHz
47pf series with 5.0uhy resonant about 10.4 MHz
Is this correct?
Brian - WA5RDG

MONEYSMITH

THIS BOARD HAS A MEGA328P CHIP. I HAVE NO INFORMATION ON THE BOARD.

I FOUND NO SI5351A CHIP?

PHOTOS ATTACHED.

W4NFR

On 11/9/2018 11:42 AM, Arv Evans wrote:
Bill W4NFR

The picture you provided is the back side of an Arduino Nano board.  The crystals on this PCB
have nothing to do with the transmitting frequency of your transceiver.  The SI5351a frequency
synthesizer is a small 10-pin MSOP IC, or 20-pin QFN IC.  It should be clearly labeled on the
top as an Si5351A device.  Do you have a picture of the Raduino board with its Si5351A chip
and crystal?

Arv  K7HKL
_._

On Fri, Nov 9, 2018 at 11:20 AM MONEYSMITH <w4nfr@...> wrote:

HERE IS A PHOTO OF BOARD AND CRYSTAL.

W4NFR

On 11/9/2018 9:57 AM, Mvs Sarma wrote:
OMG. acidentally crept in perhaps .

regards
sarma
vu3zmv

On Fri, Nov 9, 2018 at 10:50 PM MONEYSMITH <w4nfr@...> wrote:

I OPENED UP MY uBITX  AND TOOK A LOOK AT THE S1535A BOARD. THE CRYSTAL HAS 20.0 STAMPED ON IT INSTEAD OF 25.0 MHZ?

On 11/8/2018 5:59 PM, RCC WB5YYM wrote:

 This email has been checked for viruses by AVG antivirus software. www.avg.com

Re: Transmit Problem

William R Maxwell

Ooops, hit the wrong key. Yes, 100 nF.

Re: Need Source for Baofeng Mic Sockets

Scot McMath

Thanks Doug!

Gordon Gibby <ggibby@...>

look in your software and see what frequency is set for the crystal.
use a script that puts the oscillator right on a known frequency (best to use the crystal frequency)
calculate how far off it is, calculte the real crystal frequency

or use the calibration method specific to the firmware you have chosen, if you aren't able to do the above.

All mine have been 3-4 kilohertz off from the crystals "stated"' frequency. Putting in the correct constant for the effective true oscillation frequency of the crystal clock is a huge step toward having accurate frequencies. Then set your BFO if needed.

This is really a short-kit and you have to apply some of your "ham-smarts" to make things work correctly.
Because you studied and passed a ham radio license exam, you're one of the few people who are enabled to make such changes to your own amateur radio gear! Take advantage and develop your knowledge and skills!!!

Gordon

________________________________________
From: BITX20@groups.io <BITX20@groups.io> on behalf of Vince Vielhaber <vev@...>
Sent: Friday, November 9, 2018 2:55 PM
To: BITX20@groups.io
Subject: Re: [BITX20] DIGITAL FREQUENCY READOUT

To see the 25MHz xtal on mine I had to pull the display.

Vince.

On 11/09/2018 02:42 PM, Arv Evans wrote:
Bill W4NFR

The picture you provided is the back side of an Arduino Nano board. The
crystals on this PCB
have nothing to do with the transmitting frequency of your transceiver.
The SI5351a frequency
synthesizer is a small 10-pin MSOP IC, or 20-pin QFN IC. It should be
clearly labeled on the
top as an Si5351A device. Do you have a picture of the Raduino board
with its Si5351A chip
and crystal?

Arv K7HKL
_._

On Fri, Nov 9, 2018 at 11:20 AM MONEYSMITH <w4nfr@...
<mailto:w4nfr@...>> wrote:

HERE IS A PHOTO OF BOARD AND CRYSTAL.

W4NFR

On 11/9/2018 9:57 AM, Mvs Sarma wrote:
OMG. acidentally crept in perhaps .

regards
sarma
vu3zmv

On Fri, Nov 9, 2018 at 10:50 PM MONEYSMITH <w4nfr@...
<mailto:w4nfr@...>> wrote:

I OPENED UP MY uBITX AND TOOK A LOOK AT THE S1535A BOARD. THE
CRYSTAL HAS 20.0 STAMPED ON IT INSTEAD OF 25.0 MHZ?

On 11/8/2018 5:59 PM, RCC WB5YYM wrote:

------------------------------------------------------------------------
AVG logo <https://urldefense.proofpoint.com/v2/url?u=https-3A__www.avg.com_internet-2Dsecurity&d=DwICaQ&c=pZJPUDQ3SB9JplYbifm4nt2lEVG5pWx2KikqINpWlZM&r=3ELgZgmTnPzGsfvQxkd1S_2NGLYM8sHTxVCQKFxhVXQ&m=mAUii3YaxPtywhZnzMLlmMvPiPtMo5OwMNFv6xTOoAo&s=6K1mVgDOZquT0Umhtr4HP-ThrOMYwjPKIsLmBo1l8G0&e=>

This email has been checked for viruses by AVG antivirus
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--

Vince Vielhaber

To see the 25MHz xtal on mine I had to pull the display.

Vince.

On 11/09/2018 02:42 PM, Arv Evans wrote:
Bill W4NFR

The picture you provided is the back side of an Arduino Nano board. The
crystals on this PCB
have nothing to do with the transmitting frequency of your transceiver.
The SI5351a frequency
synthesizer is a small 10-pin MSOP IC, or 20-pin QFN IC. It should be
clearly labeled on the
top as an Si5351A device. Do you have a picture of the Raduino board
with its Si5351A chip
and crystal?

Arv K7HKL
_._

On Fri, Nov 9, 2018 at 11:20 AM MONEYSMITH <w4nfr@...
<mailto:w4nfr@...>> wrote:

HERE IS A PHOTO OF BOARD AND CRYSTAL.

W4NFR

On 11/9/2018 9:57 AM, Mvs Sarma wrote:
OMG. acidentally crept in perhaps .

regards
sarma
vu3zmv

On Fri, Nov 9, 2018 at 10:50 PM MONEYSMITH <w4nfr@...
<mailto:w4nfr@...>> wrote:

I OPENED UP MY uBITX AND TOOK A LOOK AT THE S1535A BOARD. THE
CRYSTAL HAS 20.0 STAMPED ON IT INSTEAD OF 25.0 MHZ?

On 11/8/2018 5:59 PM, RCC WB5YYM wrote: